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How your hormones impact your immune system

molecules, hormones, dan impact on body

Last week, we had a look at the 2 main things that you can do (for free) to support your immune system - go back to last week’s article here.

Today, I’d like to elaborate a bit more on how our hormone levels can impact our immune system: Have you ever felt like you’re getting the flu just before your period but it actually never came? Or just feeling very frail the week before your menses are coming on?

I can assure you: you’re not making this up! It’s actually “normal” because this is the time when an egg will normally settle in your uterine lining to grow and therefore women’s nature is made that way: our immune function is low during that time to avoid that your body might reject that egg nestling in.

There’s an intricate relationship between your hormone levels and your immune system! I certainly experienced it this month with low estrogen levels making me feel more tired and frail. In this blog post, we'll explore the connection between hormone levels and the immune system, and how they interact to protect and regulate our health.

First off, (as always): your stress hormones: When you're under stress, your body releases stress hormones like cortisol. Cortisol can have both positive and negative effects on your immune system. In the short term, it can help your immune system respond to immediate threats. However, chronic stress and elevated cortisol levels can suppress your immune system, making you more vulnerable to infections. And sometimes this actually means that you’re not getting sick at all, because your immune system is so depleted that it can’t actually mount a response anymore.

Your sex hormones have a big impact too: they can influence your body's response to infections and autoimmune diseases: estrogens as enhancers at least of the humoral immunity and androgens (testosterone, DHT and others) and progesterone (and glucocorticoids like cortisol) as natural immune-suppressors. Source

  • Hormones can modulate your body's inflammatory response: for example, pro-inflammatory hormones like interleukins and tumor necrosis factor (TNF) can activate immune responses, leading to inflammation. Conversely, anti-inflammatory hormones, such as glucocorticoids from your adrenal glands (such as cortisol), help regulate the immune response and prevent excessive inflammation. An imbalance in these hormones can result in chronic inflammation, contributing to autoimmune diseases and other health issues. So chronic stress can reduce the body's ability to fight off infections.

  • Hormones play a critical role in the development of the immune system: for example, during puberty, changes in sex hormones affect the maturation of the immune system. Moreover, hormones like growth hormone are essential for the development of immune cells.

  • Sex hormones can lead to differences in the immune response between men and women: estrogen, for instance, can enhance the immune system, while testosterone will suppress it. This could explain why women are often more resistant to infections but are also more prone to autoimmune diseases.

The impact of sex hormones on immune defense and reactions is a fascinating area of research! Here's a more detailed look at how sex hormones influence the immune system of men and women:

Estrogen and Immune Enhancement:

  • Enhanced Immune Response: Estrogen is known to enhance the immune response. Studies have shown that estrogen can promote the production of antibodies, stimulate the activity of natural killer cells (which target infected or abnormal cells), and increase the production of anti-inflammatory cytokines. These effects contribute to a more robust immune defense in women. By the way: elevated levels of estrogens are also associated with improved outcomes of coronavirus infections - although there’s also studies saying that it may be the lower testosterone levels: in my opinion it’s probably both!

  • Autoimmune Diseases: While estrogen can strengthen the immune system, it may also play a role in the higher prevalence of autoimmune diseases among women. Autoimmune diseases occur when the immune system mistakenly targets healthy cells and tissues. Estrogen may contribute to the increased incidence of autoimmune diseases by promoting immune cell activity. Conditions like rheumatoid arthritis, lupus, and multiple sclerosis are more common in women.

Women have a higher incidence and prevalence of autoimmune diseases than men, and 85% or more patients of multiple autoimmune diseases are female. Source

In general, menopause, and the subsequent reduction in estrogen, is associated with an increase in inflammation and the development of chronic conditions in a variety of organ systems. Source

"While it is difficult to attribute these changes solely to reduced estrogen levels, sudden losses in estrogen due to oophorectomies in premenopausal women can lead to similar outcomes [Source,Source]. This work also demonstrated that treatment with estrogen therapy can ameliorate the severity of some symptoms. These findings support the specific importance of estrogen to immune health, as opposed the general effects of aging."

Progesterone and Immune Suppression and Inflammation

Understanding the role of progesterone in the immune system is essential not only for reproductive health but also for developing treatments for autoimmune diseases and managing inflammatory responses. Research in this area continues to uncover how sex hormones, including progesterone, influence the immune system and overall health:

  • One of the most well-known roles of progesterone in the immune system is its contribution to immune tolerance during pregnancy. The maternal immune system must adapt to accommodate the developing fetus. Progesterone inhibits the activity of certain immune cells, such as T cells, which are responsible for detecting and destroying cells that are recognized as foreign. By dampening the immune response, progesterone helps prevent the rejection of the fetus. And this happens every month, even if you’re not pregnant!

  • Progesterone has anti-inflammatory properties: it can reduce the production of pro-inflammatory cytokines, which are signaling molecules that promote inflammation. This anti-inflammatory effect can help mitigate excessive inflammation and tissue damage.

  • Progesterone can affect the activity of immune cells, such as macrophages and natural killer cells. It can either enhance or suppress their function, depending on the context and the specific immune response needed.

Autoimmune Diseases and Progesterone Therapy: Given its immunosuppressive properties, progesterone therapy may have a positive effect on multiple sclerosis and rheumatoid arthritis. Progesterone therapy can help modulate the immune response and reduce the severity of these conditions. This is only true for bio-identical progesterone though. Source

Testosterone and Immune Suppression:

Testosterone tends to have an immunosuppressive effect. It can reduce your body's immune response, making men more susceptible to certain infections. This may explain why men often have a higher risk of infections, including viral infections like the flu and COVID-19.

Paradoxically, the immunosuppressive effect of testosterone might have a protective role in some situations. For instance, in cases of severe inflammatory responses (as seen in some autoimmune diseases or sepsis), the immunosuppressive effect of testosterone can actually help mitigate an excessive immune response, preventing damage to healthy tissues.

Maintaining hormone balance, managing stress, and adopting a healthy lifestyle can all contribute to a robust immune system.

I hope that you agree with me that understanding the interactions between sex hormones and the immune system is vital for tailoring treatments and interventions for various diseases, as well as for developing strategies that consider these hormonal differences to optimize health outcomes in both men and women.

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